Organic light-emitting device

ABSTRACT

An organic light-emitting device including a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, wherein the organic layer includes a first compound represented by Formula 1, below, and a second compound represented by Formula 2, below,

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2014-0154730, filed on Nov. 7, 2014, in the Korean Intellectual Property Office, and entitled: “Organic Light-Emitting Device,” is incorporated by reference herein in its entirety.

BACKGROUND

1. Field

Embodiments relate to an organic light-emitting device.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that have wide viewing angles, high contrast ratios, short response times, and excellent luminance, driving voltage, and response speed characteristics, and produce multicolored images.

The organic light-emitting devices may include an anode, a hole transport region, an emission layer, an electron transport region, and a cathode, which are sequentially stacked. Holes provided from the anode may move toward the emission layer through the hole transport region, and electrons provided from the cathode may move toward the emission layer through the electron transport region. Carriers, such as the holes and the electrons, may be recombined in the emission layer to produce excitons. These excitons may change from an excited state to a ground state, thereby generating light.

SUMMARY

Embodiments are directed to an organic light-emitting device.

The embodiments may be realized by providing an organic light-emitting device including a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, wherein the organic layer includes a first compound represented by Formula 1, below, and a second compound represented by Formula 2, below,

wherein, in Formulae 1 and 2, Naph is a naphthylene group, L is a C₆-C₄₀ arylene group or a C₁-C₄₀ heteroarylene group, HAr is a group represented by one of Formulae 3 and 4 below,

wherein, X₁ and X₂ are each independently N or C—*, and at least one of X₁ and X₂ is C—*, X₃ and X₄ are each independently N or CH, x₁ and y₁ are each independently 0 or 1, x₂ and y₂ are each independently 0 or 1, R₁ to R₈ are each independently selected from a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₂-C₂₀ alkenyl group, a substituted or unsubstituted C₂-C₂₀ alkynyl group, a substituted or unsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₄₀ aryl group, a substituted or unsubstituted C₁-C₄₀ heteroaryl group, a substituted or unsubstituted C₅-C₄₀ aryloxy group, a substituted or unsubstituted C₅-C₄₀ arylthio group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom or a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; at least one substituent of the substituted C₁-C₂₀ alkyl group, the substituted C₂-C₂₀ alkenyl group, the substituted C₂-C₂₀ alkynyl group, the substituted C₁-C₂₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₄₀ aryl group, the substituted C₁-C₄₀ heteroaryl group, the substituted C₅-C₄₀ aryloxy group, the substituted C₅-C₄₀ arylthio group, the substituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, and the substituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group is selected from a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₄₀ aryl group, a C₁-C₄₀ heteroaryl group, a C₅-C₄₀ aryloxy group, a C₅-C₄₀ arylthio group, a monovalent C₆-C₄₀ non-aromatic condensed polycyclic group, a monovalent C₆-C₄₀ non-aromatic heterocondensed polycyclic group, and —Si(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group, a is an integer of 0 to 7, b is an integer of 0 to 2, c is an integer of 1 to 3, d to h are each independently an integer of 0 to 4, i is an integer of 0 to 3, and * represents a binding site to a neighboring atom.

L in Formula 1 may be selected from a phenylene group, a naphthylene group, a phenanthrenylene group, and an anthrylene group; and a phenylene group, a naphthyl group, a phenanthrenyl group, and an anthryl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, C₁-C₁₀ alkoxy group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group.

L in Formula 1 may be a group represented by Formula 4A below:

wherein, in Formula 4A, * and *′ may represent binding sites to neighboring atoms, p₁ may be an integer of 0 to 4, and Z₁₁ may be at least one selected from a deuterium atom, a halogen atom, a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), each substituted with at least one of a deuterium atom and a halogen atom.

L in Formula 1 may be a group represented by any one of Formulae 5A to 5E below, in which * and *′ represent binding sites to neighboring atoms:

HAr in Formula 2 may be a group represented by any one of Formulae 6A to 6E below:

wherein, in Formulae 6A to 6E, Z₂₁ to Z₂₃ may each independently be selected from a deuterium atom, a halogen atom, a C₁-C₄ alkyl group, a C₆-C₂₀ aryl group, a C₁-C₂₀ heteroaryl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), in which Q₃₁ to Q₃₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₂₀ aryl group, q1 may be an integer of 0 to 4, q2 may be an integer of 1 or 2, q3 may be an integer of 0 to 3, and * represents a binding site to a neighboring atom.

HAr in Formula 2 may be a group represented by any one of Formulae 7A to 7E below, in which * represents a binding site to a neighboring atom:

R₁ to R₈ may each independently be selected from a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, a hexacenyl group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom or a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, and a hexacenyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, a C₂-C₁₀ alkenyl group, a C₂-C₁₀ alkynyl group, a C₁-C₁₀ alkoxy group, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₁₀ alkyl group, or a C₆-C₂₀ aryl group.

R₁ to R₈ may each independently be selected from a deuterium atom, a halogen atom, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₇ are each independently a hydrogen atom, a C₁-C₄ alkyl group, or a C₆-C₁₀ aryl group, or R₁ to R₈ may each independently be a group represented by any one of Formulae 8A to 8C below:

wherein, in Formulae 8A to 8C, Z₃₁ to Z₃₃ may each independently be selected from a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, a C₆-C₄₀ aryl group, a C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇); a C₁-C₂₀ alkyl group substituted with at least one of a deuterium atom and a halogen atom; and a C₆-C₄₀ aryl group and a C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, each substituted with at least one of a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, and a C₆-C₂₀ aryl group; r1 may be an integer of 0 to 5, r2 may be an integer of 0 to 7, r3 may be an integer of 0 to 10, and * represents a binding site to a neighboring atom.

R₁ to R₈ may each independently be selected from a deuterium atom and a halogen atom, or R₁ to R₈ may each independently be a group represented by any one of Formulae 9A to 9J below:

wherein, in Formulae 9A to 9J, * represents a binding site to a neighboring atom.

c may be 1, a and b may each independently be 0 or 1, and d, e, f, g, h, and i may each be 0.

R₁ and R₂ may each independently be selected from a deuterium atom, a halogen atom, a methyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom, a methyl group, or a phenyl group; and a phenyl group, a naphthyl group, and a pentalenyl group, each substituted with at least one of a deuterium atom, a halogen atom, and a methyl group; d, e, f, g, h, and i may each be 0, L may be selected from a phenylene group; or a phenylene group and a naphthylene group, each substituted with at least one selected from a deuterium atom, a halogen atom, and a phenyl group.

HAr may be a group represented by Formula 3.

HAr may be a group represented by Formula 4, x₂ may be 1, and y₁ may be 0.

The first compound represented by Formula 1 may be one of Compounds 1-1 to 1-36 below:

The second compound represented by Formula 2 may be one of Compounds 2-1 to 2-5 below:

The first compound and the second compound may be included in the emission layer.

A weight ratio of the first compound to the second compound may be about 20:80 to about 80:20.

The emission layer may further include a dopant, the dopant including an organometallic compound that includes iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), or copper (Cu).

The organic light-emitting device may further include a hole transport region between the first electrode and the emission layer.

The organic light-emitting device may further include an electron transport region between the second electrode and the emission layer.

BRIEF DESCRIPTION OF THE DRAWING

Features will be apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which:

the FIGURE illustrates a schematic cross-sectional view of a structure of an organic light-emitting device according to an exemplary embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter with reference to the accompanying drawing; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.

In the drawing FIGURE, the dimensions of layers and regions may be exaggerated for clarity of illustration. Like reference numerals refer to like elements throughout.

As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

the FIGURE illustrates a schematic cross-sectional view of a structure of an organic light-emitting device 10 according to an exemplary embodiment.

Referring to the FIGURE, the organic light-emitting device 10 may include a first electrode 110, an organic layer 150, and a second electrode 190.

A substrate may be additionally disposed beneath the first electrode 110 or on the second electrode 190. The substrate may be a glass substrate or a transparent plastic substrate, each of which has excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water proofness.

The first electrode 110 may be formed by, e.g., depositing or sputtering a material for forming the first electrode on the substrate. When the first electrode 110 is an anode, the material for forming the first electrode may be selected from materials with a high work function to facilitate hole injection. The first electrode 110 may be a transmissive electrode, a semi-transmissive electrode, or a transparent electrode. The material for forming the first electrode may have characteristics of excellent transparency and conductivity, and examples thereof may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), and zinc oxide (ZnO). In an implementation, the material for forming the first electrode may be at least one selected from magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), and magnesium-silver (Mg—Ag) to form a semi-transmissive electrode or a reflective electrode as the first electrode 110. The first electrode 110 may have a single-layer structure or a multi-layer structure consisting two or more different layers. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO.

The organic layer 150 may be disposed on the first electrode 110. The organic layer 150 may include an emission layer. The organic layer 150 may further include an electron transport region between the emission layer and the second electrode 190, in addition to a hole transport region between the first electrode 110 and the emission layer.

The hole transport region may include at least one of a hole injection layer (HIL), a hole transport layer (HTL), a buffer layer, and an electron blocking layer (EBL), and the electron transport region may include at least one of a hole blocking layer (HBL), an electron transport layer (ETL), and an electron injection layer (EIL).

The hole transport region may have a single-layer structure including a single material, a single-layer structure including a plurality of different materials, or a multi-layer structure including a plurality of different materials.

For example, the hole transport region may have a single-layer structure including a plurality of different materials, or may have a structure of HIL/HTL, a structure of HIL/HTL/buffer layer, a structure of HIL/buffer layer, a structure of HTL/buffer layer, a structure of HIL/HTL/EBL, or a structure of HTL/EBL, each of which layers are sequentially stacked in the stated order from the first electrode 110.

When the hole transport region includes an HIL, the HIL may be formed on the first electrode 110 by using various methods, e.g., vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, or laser induced thermal imaging (LITI).

When the HIL is formed by vacuum deposition, deposition conditions may vary according to a compound used to form the HIL and a structure of the HIL, e.g., the deposition conditions include a deposition temperature in a range of about 100° C. to about 500° C., a vacuum pressure in a range of about 10⁻⁸ torr to about 10⁻³ torr, and/or a deposition rate in a range of about 0.01 Å/sec to about 100 Å/sec.

When the HIL is formed by spin coating, spin coating conditions may vary according to a compound used to form the HIL and a structure of the HIL, e.g., the spin coating conditions include a coating speed in a range of about 2,000 rpm to about 5,000 rpm, and/or a temperature at which a heat treatment is performed may be in a range of about 80° C. to about 200° C.

When the hole transport region includes an HTL, the HTL may be formed on the first electrode 110 or on the HIL by using various methods, e.g., vacuum deposition, spin coating, casting, LB deposition, ink-jet printing, laser-printing, or LITI. When the HTL is formed by vacuum deposition and spin coating, deposition and coating conditions for forming the HTL may be determined by referring to the deposition and coating conditions for forming the HIL.

The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine) (TCTA), polyaniline/dodecylbenzenesulfonic acid:polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonicacid:polyaniline (Pani/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201 below, and a compound represented by Formula 202 below:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from a substituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstituted heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀ cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀ arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.

At least one substituent of the substituted C₃-C₁₀ cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀ heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, and the substituted divalent non-aromatic condensed heteropolycyclic group may be selected from:

a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₂₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₂₀₁)(Q₂₀₂), —Si(Q₂₀₃)(Q₂₀₄)(Q₂₀₅), and —B(Q₂₀₆)(Q₂₀₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₂₁₁)(Q₂₁₂), —Si(Q₂₁₃)(Q₂₁₄)(Q₂₁₅), and —B(Q₂₁₆)(Q₂₁₇); and

—N(Q₂₂₁)(Q₂₂₂), —Si(Q₂₂₃)(Q₂₂₄)(Q₂₂₅), and —B(Q₂₂₆)(Q₂₂₇);

xa1 to xa4 may each independently be selected from 0, 1, 2, and 3;

xa5 may be selected from 1, 2, 3, 4, and 5;

R₂₀₁ to R₂₀₅ may each independently be selected from a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₂₃₁)(Q₂₃₂), —Si(Q₂₃₃)(Q₂₃₄)(Q₂₃₅), and —B(Q₂₃₆)(Q₂₃₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; and

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₂₄₁)(Q₂₄₂), —Si(Q₂₄₃)(Q₂₄₄)(Q₂₄₅), and —B(Q₂₄₆)(Q₂₄₇),

wherein Q₂₀₁ to Q₂₀₇, Q₂₁₁ to Q₂₁₇, Q₂₂₁ to Q₂₂₇, Q₂₃₁ to Q₂₃₇, and Q₂₄₁ to Q₂₄₇ may each independently be selected from a hydrogen atom, a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; and

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthrylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group; and

a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthrylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

xa1 to xa4 may each independently be 0, 1, or 2;

xa5 may be 1, 2, or 3;

R₂₀₁ to R₂₀₅ may each independently be selected from a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, an azulenyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, but the embodiment is not limited thereto.

The compound represented by Formula 201 above may be represented by Formula 201A below.

For example, the compound represented by Formula 201 above may be represented by Formula 201A-1 below.

The compound represented by Formula 202 above may be represented by Formula 202A below.

In Formulae 201A, 201A-1, and 202A, L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ may be understood by referring to the description provided herein, and R₂₁₁ and R₂₁₂ may be understood by referring to the description provided in connection with R₂₀₃, and

R₂₁₃ to R₂₁₇ may each independently be selected from a hydrogen atom, a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formulae 201A, 201A-1, and 202A, L₂₀₁ to L₂₀₃ may each independently be from a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthrylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group; and

a phenylene group, a naphthylenylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylene group, an anthrylene group, a pyrenylene group, a chrysenylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, a quinolinylene group, an isoquinolinylene group, a quinoxalinylene group, a quinazolinylene group, a carbazolylene group, and a triazinylene group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

xa1 to xa3 may each independently be 0 or 1;

R₂₀₃, R₂₁₁, and R₂₁₂ may each independently be selected from a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

R₂₁₃ and R₂₁₄ may each independently be selected from a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

, a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

R₂₁₅ and R₂₁₇ may each independently be selected from a hydrogen atom, a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, and a triazinyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

xa5 may be 1 or 2.

In an implementation, in Formulae 201A and 201A-1, R₂₁₃ and R₂₁₄ may be fused to each other to form a saturated or unsaturated ring.

The compound represented by Formula 201 above and the compound represented by Formula 202 above may include Compounds HT1 to HT20 below.

A thickness of the hole transport region may be in a range of about 100 Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å. When the hole transport region includes both an HIL and an HTL, a thickness of the HIL may be in a range of about 100 Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å, and a thickness of the HTL may be in a range of about 50 Å to about 2,000 Å, e.g., about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the HIL, and the HTL are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.

In addition to the materials described above, the hole transport region may further include a charge-generation material for the improvement of conductive characteristics. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The charge-generation material may be, e.g., a p-dopant. The p-dopant may be a quinone derivative, such as a tetracyanoquinodimethane (TCNQ) and tetrafluorotetracyanoquinodimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide and a molybdenum oxide; and 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HATCN), but is not limited thereto.

The hole transport region may further include, in addition to the HIL, the HTL, and an emission auxiliary layer, at least one of a buffer layer and an EBL. The buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, a light-emission efficiency of a formed organic light-emitting device may be improved. For use as a material for forming the buffer layer, a material for forming the hole transport region may be used. The EBL may help prevent electron injection from the electron transport region. For example, an example of a material for forming the EBL may include mCP below, but is not limited thereto.

The emission layer may be formed on the first electrode 110 or on the hole transport region by using various methods, e.g., vacuum deposition, spin coating, casting, LB deposition, ink-jet printing, laser-printing, or LITI. When the emission layer is formed by vacuum deposition and spin coating, deposition and coating conditions for forming the emission layer may be determined by referring to the deposition and coating conditions for forming the HIL.

When the organic light-emitting device 10 is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer, according to a red subpixel, a green subpixel, and a blue subpixel, respectively. In an implementation, the emission layer may have a structure of a red emission layer, a green emission layer, and a blue emission layer, each of which layers are sequentially stacked in this stated order, or may have a structure where a red light-emitting material, a green light-emitting material, and a blue light-emitting material are mixed regardless of layer division, so that the emission layer may emit white light. When the emission layer emits white light, the device may further include a color conversion layer or a color filter.

The emission layer may include a host and a dopant.

The host may include a first compound represented by Formula 1 below and a second compound represented by Formula 2 below.

In Formulae 1 and 2,

Naph may be a naphthylene group,

L may be a C₆-C₄₀ arylene group or a C₁-C₄₀ heteroarylene group,

HAr may be a group represented by one of Formulae 3 and 4 below.

X₁ and X₂ may each independently be, e.g., N or C—*, and at least one of X₁ and X₂ may be C—*. For example, the * in C—* and in Formula 4 may represent a binding site to a nitrogen atom of the carbazole moiety of Formula 2.

X₃ and X₄ may each independently be, e.g., N or CH,

x₁ and y₁ may each independently be, e.g., 0 or 1,

x₂ and y₂ may each independently be, e.g., 0 or 1,

R₁ to R₈ may each independently be selected from or include, e.g., a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₂-C₂₀ alkenyl group, a substituted or unsubstituted C₂-C₂₀ alkynyl group, a substituted or unsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted heterocycloalkenyl group, a substituted or unsubstituted C₆-C₄₀ aryl group, a substituted or unsubstituted C₁-C₄₀ heteroaryl group, a substituted or unsubstituted C₅-C₄₀ aryloxy group, a substituted or unsubstituted C₅-C₄₀ arylthio group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ may each independently be a hydrogen atom, a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ may be each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group.

In an implementation, at least one substituent of the substituted C₁-C₂₀ alkyl group, the substituted C₂-C₂₀ alkenyl group, the substituted C₂-C₂₀ alkynyl group, the substituted C₁-C₂₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₂₀ heterocycloalkyl group, the substituted C₃-C₂₀ cycloalkenyl group, the substituted C₁-C₂₀ heterocycloalkenyl group, the substituted C₆-C₄₀ aryl group, the substituted C₁-C₄₀ heteroaryl group, the substituted C₅-C₄₀ aryloxy group, the substituted C₅-C₄₀ arylthio group, the substituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, the substituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group may be selected from:

a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₄₀ aryl group, a C₁-C₄₀ heteroaryl group, a C₅-C₄₀ aryloxy group, a C₅-C₄₀ arylthio group, a C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, a C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group, and —Si(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ may each independently be a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group.

a may be, e.g., an integer of 0 to 7,

b may be, e.g., an integer of 0 to 2,

c may be, e.g., an integer of 1 to 3,

d to h may each independently be, e.g., an integer of 0 to 4,

i may be, e.g., an integer of 0 to 3, and,

* may indicate a binding site to a neighboring atom (e.g., the nitrogen in Formula 2).

In Formula 1,

L may be selected from, e.g.,

a phenylene group, a naphthylene group, a phenanthrenylene group, and an anthrylene group; and

a phenylene group, a naphthyl group, a phenanthrenyl group, and an anthryl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ may be each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group.

In an implementation, L may be a group represented by Formula 4A below.

In Formula 4A, p₁ may be, e.g., an integer of 0 to 4, and Z₁₁ may be selected from, e.g.,

a deuterium atom, a halogen atom, a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ may be each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, —Si(Q₂₁)(Q₂₂)(Q₂₃), each substituted with at least one of a deuterium atom and a halogen atom.

For example, L may be a group represented by any one of Formulae 5A to 5E below.

In an implementation, Formula 2, HAr may be a group represented by any one of Formulae 6A to 6E below.

In Formulae 6A to 6E,

Z₂₁ to Z₂₃ may each independently be selected from, e.g., a deuterium atom, a halogen atom, a C₁-C₄ alkyl group, a C₆-C₂₀ aryl group, a C₁-C₂₀ heteroaryl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), in which Q₃₁ to Q₃₃ may each independently be a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₂₀ aryl group,

q1 may be, e.g., an integer of 0 to 4,

q2 may be, e.g., an integer of 1 or 2, and

q3 may be, e.g., an integer of 0 to 3.

In an implementation, HAr may be a group represented by any one of Formulae 7A to 7E below.

In an implementation, in Formulae 1 to 4, R₁ to R₈ may each independently be selected from, e.g.,

a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, a hexacenyl group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ may each independently be a hydrogen atom, or a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ may be each independently a hydrogen atom, a C₁-C₂₀ alkyl group or a C₆-C₄₀ aryl group;

a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ may each independently be a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, and a hexacenyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, a C₂-C₁₀ alkenyl group, a C₂-C₁₀ alkynyl group, a C₁-C₁₀ alkoxy group, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ may each independently be a hydrogen atom, a C₁-C₁₀ alkyl group, or a C₆-C₂₀ aryl group.

In an implementation, R₁ to R₈ may each independently be selected from, e.g., a deuterium atom, a halogen atom, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₇ may each independently be selected from a hydrogen atom, a C₁-C₄ alkyl group, or a C₆-C₁₀ aryl group, or may each independently be, e.g., a group represented by any one of Formulae 8A to 8C below.

In Formulae 8A to 8C,

Z₃₁ to Z₃₃ may each independently be selected from, e.g.,

a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, a C₆-C₄₀ aryl group, a monovalent C₆-C₄₀ non-aromatic condensed polycyclic group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇);

a C₁-C₂₀ alkyl group substituted with at least one of a deuterium atom and a halogen atom; and

a C₆-C₄₀ aryl group and a monovalent C₆-C₄₀ non-aromatic condensed polycyclic group, each substituted with at least one of a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, and a C₆-C₂₀ aryl group.

r1 may be, e.g., an integer of 0 to 5,

r2 may be, e.g., an integer of 0 to 7, and

r3 may be, e.g., an integer of 0 to 10.

In an implementation, R₁ to R₈ may each independently be selected from, e.g., a deuterium atom and a halogen atom, or may each independently be, e.g., a group represented by any one of Formulae 9A to 9J below.

In an implementation, in Formula 1, a, b, and c may each independently be 0 or 1 (e.g., c may be 1), and in Formula 2, d, e, f, g, h, and i may each be 0.

In an implementation, R₁ to R₈ may each independently be selected from, e.g., a deuterium atom, a halogen atom, a methyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₅ to Q₇ may each independently be a hydrogen atom, a methyl group, or a phenyl group; and a phenyl group, a naphthyl group, and a pentalenyl group, each substituted with at least one of a deuterium atom, a halogen atom, and a methyl group,

d, e, f, g, h, and i may be 0,

In an implementation, L may be selected from, e.g., a phenylene group; and a phenylene group and a naphthylene group, each substituted with at least one of a deuterium atom, a halogen atom, a phenyl group, and a deuterium.

In an implementation, HAr may be a group represented by Formula 3 above,

in which X₁ and X₂ may each independently be, e.g., N or C—* and at least one of X₁ and X₂ may be C—*,

X₃ and X₄ may each independently be, e.g., N or CH, and

x₁ and y₁ may each independently be, e.g., 0 or 1.

In an implementation, HAr may be, e.g., a group represented by Formula 4 above, wherein x₂ may be 1 and y₁ may be 0.

In an implementation, the first compound represented by Formula 1 above may be, e.g., any one of Compounds 1 to 36 below.

In an implementation, the second compound represented by Formula 2 above may be, e.g., any one of Compounds 2-1 to 2-5 below.

The host may include the first compound and the second compound. In an implementation, a weight ratio of the first compound to the second compound may be about 1:9 to about 9:1, e.g., about 2:8 to about 8:2. In an implementation, a weight ratio of the first compound to the second compound may be about 3:7 to about 7:3. The weight ratio may vary according to the balance of charges in the organic light-emitting device. In an implementation, the weight ratio may vary according to the mobility of charges of the HTL and the ETL or the energy level difference in the emission layer.

The second compound represented by Formula 2 above may have a triplet energy level of at least 2.75 eV, and accordingly, may have a higher triplet energy than that of CBP. In addition, the second compound may have a higher triplet energy than that of a typical dopant (2.7 eV), and thus, in the case of using the second compound as a host, the host may help reduce and/or prevent the reversal flow of the energy back to a dopant, thereby improving a light-emission efficiency of the organic light-emitting device.

In an implementation, in the case of using a mixed host of the first compound and the second compound, a balance between the electrons and the holes may be improved so that the lifespan of the organic light-emitting device may also be improved, resulting in the achievement of a high efficiency of the organic light-emitting device.

The dopant may be a phosphorescent dopant.

For example, the phosphorescent dopant may include an organometallic compound including at least one of iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), and Cu (copper).

In an implementation, the phosphorescent dopant may include, e.g., a compound represented by Formula 401, below.

In Formula 401,

M may be selected from, e.g., Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Rh, and Cu;

X₄₀₁ to X₄₀₄ may each independently be, e.g., nitrogen or carbon;

ring A₄₀₁ and ring A₄₀₂ may each independently be selected from or include, e.g., a substituted or unsubstituted benzene, a substituted or unsubstituted naphthalene, a substituted or unsubstituted fluorene, a substituted or unsubstituted spiro-fluorene, a substituted or unsubstituted indene, a substituted or unsubstituted pyrrole, a substituted or unsubstituted thiophene, a substituted or unsubstituted furan, a substituted or unsubstituted imidazole, a substituted or unsubstituted pyrazole, a substituted or unsubstituted thiazole, a substituted or unsubstituted isothiazole, a substituted or unsubstituted oxazole, a substituted or unsubstituted isooxazole, a substituted or unsubstituted pyridine, a substituted or unsubstituted pyrazine, a substituted or unsubstituted pyrimidine, a substituted or unsubstituted pyridazine, a substituted or unsubstituted quinoline, a substituted or unsubstituted isoquinoline, a substituted or unsubstituted benzoquinoline, a substituted or unsubstituted quinoxaline, a substituted or unsubstituted quinazoline, a substituted or unsubstituted carbazole, a substituted or unsubstituted benzoimidazole, a substituted or unsubstituted benzofuran, a substituted or unsubstituted benzothiophene, a substituted or unsubstituted isobenzothiophene, a substituted or unsubstituted benzoxazole, a substituted or unsubstituted isobenzoxazole, a substituted or unsubstituted triazole, a substituted or unsubstituted oxadiazole, a substituted or unsubstituted triazine, a substituted or unsubstituted dibenzofuran, and a substituted or unsubstituted dibenzothiophene.

In an implementation, at least one substituent of the substituted benzene, the substituted naphthalene, the substituted fluorene, the substituted spiro-fluorene, the substituted indene, the substituted pyrrole, the substituted thiophene, the substituted furan, the substituted imidazole, the substituted pyrazole, the substituted thiazole, the substituted isothiazole, the substituted oxazole, the substituted isoxazole, the substituted pyridine, the substituted pyrazine, the substituted pyrimidine, the substituted pyridazine, the substituted quinoline, the substituted isoquinoline, the substituted benzoquinoline, the substituted quinoxaline, the substituted quinazoline, the substituted carbazole, the substituted benzoimidazole, the substituted benzofuran, the substituted benzothiophene, the substituted isobenzothiophene, the substituted benzoxazole, the substituted isobenzoxazole, the substituted triazole, the substituted oxadiazole, the substituted triazine, the substituted dibenzofuran, and the substituted dibenzothiophene may be selected from:

a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one of a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₂-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₄₀₁)(Q₄₀₂), —Si(Q₄₀₃)(Q₄₀₄)(Q₄₀₅), and —B(Q₄₀₆)(Q₄₀₇);

a C₃-C₁₀ cycloalkyl group, a C₂-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₂-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one of a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₂-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q₄₁₁)(Q₄₁₂), —Si(Q₄₁₃)(Q₄₁₄)(Q₄₁₅), and —B(Q₄₁₆)(Q₄₁₇); and

—N(Q₄₂₁)(Q₄₂₂), —Si(Q₄₂₃)(Q₄₂₄)(Q₄₂₅), and —B(Q₄₂₆)(Q₄₂₇);

L₄₀₁ may be, e.g., an organic ligand;

xc1 may be, e.g., 1, 2, or 3; and

xc2 may be, e.g., 0, 1, 2, or 3.

L₄₀₁ may be, e.g., any one of a monovalent organic ligand, a divalent organic ligand, and a trivalent organic ligand. For example, L₄₀₁ may be selected from a halogen ligand (e.g., Cl or F), a diketone ligand (e.g., acetylacetonate, 1,3-diphenyl-1,3-propanedionate, 2,2,6,6-tetramethyl-3,5-heptanedionate, or hexafluoroacetonate), a carboxylic acid ligand (e.g., picolinate, dimethyl-3-pyrazolecarboxylate, or benzoate), a carbon monoxide ligand, an isonitrile ligand, a cyano ligand, and a phosphorus ligand (e.g., phosphine or phosphaite), but is not limited thereto.

In Formula 401, when A₄₀₁ has 2 or more substituents, the 2 or more substituents of A₄₀₁ may be linked with each other to form a saturated or unsaturated ring.

In Formula 401, when A₄₀₂ has 2 or more substituents, the 2 or more substituents of A₄₀₂ may be linked with each other to form a saturated or unsaturated ring.

In Formula 401, when xc1 is 2 or more, a plurality of ligands in Formula 401, i.e.,

may be identical to or different to each other. In Formula 401, when xc1 is 2 or more, A₄₀₁ and A₄₀₂ respectively may be each linked directly with another A₄₀₁ and A₄₀₂ of a neighboring ligand. Alternatively, A₄₀₁ and A₄₀₂ may be each linked with each other via a linking group (e.g., a C₁-C₅ alkylene group, —N(R′)-(wherein R′ is a C₁-C₁₀ alkyl group or a C₆-C₂₀ aryl group)), or —C(═O)— of a neighboring ligand.

The phosphorescent dopant may include, e.g., at least one of Ir(ppy)₂(acac), Ir(mpyp)₃, and Compounds PD1 to PD76 below, (e.g., Compound PD1 is Ir(ppy)₃ and Compound DP2 is FIrPic):

In an implementation, an amount of the dopant included in the emission layer may be, e.g., about 0.01 to about 15 parts by weight, based on 100 parts by weight of the host.

A thickness of the emission layer may be about 100 Å to about 1,000 Å, e.g., 200 Å to about 600 Å. When the thickness of the emission layer is within these ranges, excellent emission characteristics may be obtained without a substantial increase in driving voltage.

The electron transport region may include at least one of an HBL, an ETL, and an EBL.

For example, the electron transport region may have a structure of ETL/EIL or a structure of HBL/ETL/EIL, each of which layers are sequentially stacked in the stated order from the emission layer.

The electron transport region may include an HBL. When the emission layer includes a phosphorescent dopant, the HBL may be formed to help prevent diffusion of triplet excitons or holes into an ETL.

When the electron transport region includes an HBL, the HBL may be formed on the emission layer by using various methods, e.g., vacuum deposition, spin coating, casting, LB deposition, ink-jet printing, laser-printing, or LITI. When the HBL is formed by vacuum deposition and spin coating, deposition and coating conditions for forming the HBL may be determined by referring to the deposition and coating conditions for forming the HIL.

The HBL may include, e.g., at least one of bathocuproine (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), and 3,3′-[5′-[3-(3-pyridinyl)phenyl][1,1′:3′,1″-terphenyl]-3,3″-diyl]bispyridine (TmPyPB) below, but is not limited thereto.

A thickness of the HBL may be in a range of about 20 Å to about 1,000 Å, e.g., about 30 Å to about 300 Å. When the thickness of the HBL is within these ranges, excellent hole blocking characteristics may be obtained without a substantial increase in driving voltage.

The electron transport region may include an ETL. The ETL may be formed on the emission layer or on the HBL by using various methods, e.g., vacuum deposition, spin coating, casting, LB deposition, ink-jet printing, laser-printing, or LITI. When the ETL is formed by vacuum deposition and spin coating, deposition and coating conditions for forming the ETL may be determined by referring to the deposition and coating conditions for forming the HIL.

The electron transport layer may further include at least one of, e.g., BCP, Bphen above, and Alq₃, bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum (III) (Balq), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (TAZ), and 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ) below.

In an implementation, the ETL may include at least one of compounds represented by Formula 601 below: Ar₆₀₁-[(L₆₀₁)_(xe1)-E₆₀₁]_(xe2)  <Formula 601>

In Formula 601,

Ar₆₀₁ may be selected from:

a naphthalene, a heptalene, a fluorene, a spiro-fluorene, a benzofluorene, a dibenzofluorene, a phenalene, a phenanthrene, an anthracene, a fluoranthene, a triphenylene, a pyrene, a chrysene, a naphthacene, a picene, a perylene, a pentaphene, and an indenoanthracene;

a naphthalene, a heptalene, a fluorene, a spiro-fluorene, a benzofluorene, a dibenzofluorene, a phenalene, a phenanthrene, an anthracene, a fluoranthene, a triphenylene, a pyrene, a chrysene, a naphthacene, a picene, a perylene, a pentaphene, and an indenoanthracene, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₃-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₃-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a C₂-C₆₀ monovalent non-aromatic condensed polycyclic group, and —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), in which Q₃₀₁ to Q₃₀₃ may each independently be selected from a hydrogen atom, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₆-C₆₀ aryl group, and a C₂-C₆₀ heteroaryl group;

L₆₀₁ may be understood by referring to the description provided in connection with L₂₀₁;

E₆₀₁ may be selected from:

a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group; and

a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a triazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group;

xe1 may be selected from 0, 1, 2, and 3; and

xe2 may be selected from 1, 2, 3, and 4.

In an implementation, the ETL may include at least one of compounds represented by Formula 602 below.

In Formula 602,

X₆₁₁ may be N or C-(L₆₁₁)_(xe611)-R₆₁₁, X₆₁₂ may be N or C-(L₆₁₂)_(xe612)-R₆₁₂, and

X₆₁₃ may be N or C-(L₆₁₃)_(xe613)-R₆₁₃, and at least one of X₆₁₁ to X₆₁₃ may be N;

L₆₁₁ to L₆₁₆ may each independently be understood by referring to the description provided in connection with L₂₀₁;

R₆₁₁ to R₆₁₆ may each independently be selected from:

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and a triazinyl group, each substituted with at least one of a deuterium atom, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, an azulenyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthryl group, a pyrenyl group, a chrysenyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group and a triazinyl group; and

xe611 to xe616 may each independently be selected from 0, 1, 2, and 3.

The compound represented by Formula 601 and the compound represented by Formula 602 may include at least one of Compounds ET1 to ET15 below.

A thickness of the ETL may be in a range of about 100 Å to about 1,000 Å, e.g., about 150 Å to about 500 Å. When the thickness of the ETL is within these ranges, satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.

In an implementation, the ETL may further include a metal-containing material, in addition to the electron-transporting organic compounds described above.

The metal-containing material may include a Li complex. The Li complex may include, e.g., lithium quinolate (LiQ) or lithium[2-(2-hydroxyphenyl)benzothiazole] (LiBTz) below.

In an implementation, the electron transport region may include an EIL that facilitates electron injection from the second electrode 190.

The EIL may include, e.g., at least one selected from LiF, NaCl, CsF, Li₂O, and BaO.

A thickness of the EIL may be in a range of about 1 Å to about 100 Å, e.g., about 3 Å to about 90 Å. When the thickness of the EIL is within these ranges, satisfactory electron injecting characteristics may be obtained without a substantial increase in driving voltage.

Layers or regions included in the organic layer 150 may be formed by using various methods, e.g., vacuum deposition, spin coating, casting, LB deposition, ink-jet printing, laser-printing, or LITI.

The second electrode 190 may be disposed on the organic layer 150. The second electrode 190 may be a cathode, and in this regard, a material for forming the second electrode 190 may be a material having a low work function, such as a metal, an alloy, an electrically conductive compound, or a mixture thereof. Examples of the material for forming the second electrode 190 may include lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), and magnesium-silver (Mg—Ag). In an implementation, to manufacture a top emission type light-emitting device, the material for forming the second electrode 190 may be ITO or IZO, and in this regard, the second electrode 190 may be a transmissive electrode or the like

Herein, the organic light-emitting device 10 is referred to the description provided in connection with FIG. 1.

A C₁-C₆₀ alkyl group used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and detailed examples thereof are a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. A C₁-C₆₀ alkylene group used herein refers to a divalent group having the same structure as the C₁-C₆₀ alkyl group.

A C₁-C₆₀ alkoxy group used herein refers to a monovalent group represented by —OA₁₀₁ (herein A₁₀₁ is the C₁-C₆₀ alkyl group), and detailed examples thereof are a methoxy group, an ethoxy group, and an isopropyloxy group.

A C₂-C₆₀ alkenyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon double bond in the middle or terminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are an ethenyl group, a prophenyl group, and a butenyl group. A C₂-C₆₀ alkenylene group used herein refers to a divalent group having the same structure as the C₂-C₆₀ alkenyl group.

A C₂-C₆₀ alkynyl group used herein refers to a hydrocarbon group formed by substituting at least one carbon triple bond in the middle or terminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are an ethynyl group and a propynyl group. A C₂-C₆₀ alkynylene group used herein refers to a divalent group having the same structure as the C₂-C₆₀ alkynyl group.

A C₃-C₁₀ cycloalkyl group used herein refers a monovalent hydrocarbon monocyclic group having 3 to 10 carbon atoms, and detailed examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. A C₃-C₁₀ cycloalkylene group used herein refers to a divalent group having the same structure as the C₃-C₁₀ cycloalkyl group.

A C₁-C₁₀ heterocycloalkyl group used herein refers to a monovalent monocyclic group having at least one heteroatom selected from N, O, P, and S as a ring-forming atom and 1 to 10 carbon atoms, and detailed examples thereof are a tetrahydrofuranyl group and a tetrahydrothiophenyl group. A C₁-C₁₀ heterocycloalkylene group used herein refers to a divalent group having the same structure as the C₁-C₁₀ heterocycloalkyl group.

A C₃-C₁₀ cycloalkenyl group used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one double bond in the ring thereof and does not have aromacity, and detailed examples thereof are a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. A C₃-C₁₀ cycloalkenylene group used herein refers to a divalent group having the same structure as the C₃-C₁₀ cycloalkenyl group.

A C₁-C₁₀ heterocycloalkenyl group used herein refers to a monovalent monocyclic group that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Detailed examples of the C₁-C₁₀heterocycloalkenyl group are a 2,3-hydrofuranyl group and a 2,3-hydrothiophenyl group. A C₁-C₂₀ heterocycloalkenylene group used herein refers to a divalent group having the same structure as the C₁-C₁₀ heterocycloalkenyl group.

A C₆-C₆₀ aryl group used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀ arylene group used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Detailed examples of the C₆-C₆₀ aryl group are a phenyl group, a naphthyl group, an anthryl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene group each include two or more rings, the rings may be fused to each other.

A C₁-C₆₀ heteroaryl group used herein refers to a monovalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60 carbon atoms. A C₁-C₆₀ heteroarylene group used herein refers to a divalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60 carbon atoms. Detailed examples of the C₁-C₆₀ heteroaryl group are a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group each include two or more rings, the rings may be fused to each other.

A C₆-C₆₀ aryloxy group used herein indicates —OA₁₀₂ (wherein A₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used herein indicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

A monovalent non-aromatic condensed polycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, has carbon atoms only as a ring-forming atom, and has non-aromacity in the entire molecular structure. A detailed example of the monovalent non-aromatic condensed polycyclic group is a fluorenyl group. A divalent non-aromatic condensed polycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used herein refers to a monovalent group that has two or more rings condensed to each other, has heteroatoms as a ring-forming atom selected from N, O, P, and S, in addition to C, and has non-aromacity in the entire molecular structure. A detailed example of the monovalent non-aromatic condensed heteropolycyclic group is a carbazolyl group. A divalent non-aromatic condensed heteropolycyclic group used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

Q groups, where not otherwise described, may be understood by referring to descriptions of other Q groups.

Hereinafter, an organic light-emitting device according to embodiments is described in detail with reference to Examples, (Compounds below are those used in organic light-emitting devices prepared according to Examples).

The following Examples and Comparative Examples are provided in order to highlight characteristics of one or more embodiments, but it will be understood that the Examples and Comparative Examples are not to be construed as limiting the scope of the embodiments. Further, it will be understood that the embodiments are not limited to the particular details described in the Examples and Comparative Examples.

Example 1

A glass substrate to which an ITO anode was formed (available by Corning company) having a surface resistance of 15Ω/□ (500 Å) was prepared, sonicated by using isopropyl alcohol and pure water each for 10 minutes, and cleansed by the exposure to UV ozone for 10 minutes. Then, 2-TNATA was vacuum deposited on the ITO anode of the glass substrate to form a hole injection layer having a thickness of 600 Å. NPB was vacuum deposited on the HIL to form an HTL having a thickness of 300 Å.

Compound 1-5, Compound 2-1, and Ir(ppy)₃ were co-deposited on the HTL at a weight ratio of 75:15:10 to form an emission layer having a thickness of 400 Å. Alq₃ was deposited on the emission layer to form an ETL having a thickness of 300 Å. Alq₃ was vacuum deposited on the ETL to form a cathode having a thickness of 1,200 Å, thereby manufacturing an organic light-emitting device.

Example 2

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, the weight ratio of Compound 1-5, Compound 2-1, and Ir(ppy)₃ was 65:25:10 instead of 75:15:10.

Example 3

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 1-5, Compound 2-3, and Ir(ppy)₃ was 70:20:10.

Example 4

An organic light-emitting device was manufactured in the same manner as in Example 3, except that in forming the emission layer, the weight ratio of the Compound 1-5, Compound 2-3, and Ir(ppy)₃ was 60:30:10 instead of 70:20:10.

Example 5

An organic light-emitting device was manufactured in the same manner as in

Example 1, except that in forming the emission layer, a weight ratio of Compound 1-22, Compound 2-1, and Ir(ppy)₃ was 30:60:10.

Example 6

An organic light-emitting device was manufactured in the same manner as in Example 5, except that in forming the emission layer, the weight ratio of Compound 1-22, Compound 2-1, and Ir(ppy)₃ was 20:70:10 instead of 30:60:10.

Example 7

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 1-22, Compound 2-3, and Ir(ppy)₃ was 30:60:10.

Example 8

An organic light-emitting device was manufactured in the same manner as in Example 7, except that in forming the emission layer, the weight ratio of Compound 1-22, Compound 2-3, and Ir(ppy)₃ was 20:70:10 instead of 30:60:10.

Comparative Example 1

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 1-5 and Ir(ppy)₃ was 90:10.

Comparative Example 2

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 1-22 and Ir(ppy)₃ was 90:10.

Comparative Example 3

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 2-1 and Ir(ppy)₃ was 90:10.

Comparative Example 4

An organic light-emitting device was manufactured in the same manner as in Example 1, except that in forming the emission layer, a weight ratio of Compound 2-3 and Ir(ppy)₃ was 90:10.

Measurement Data

The organic light-emitting devices prepared according to Examples 1 to 8 and Comparative Examples 1 to 4 were evaluated in terms of current density, current efficiency, and lifespan (T₉₀) characteristics, and obtained data were analyzed by an IVL measuring device (PhotoResearch PR650, Keithley 238). The lifespan T₉₀ data were obtained upon operation, when luminance of the organic light-emitting device reached 90% with respect to initial luminance 100% (at 9,000 nit).

TABLE 1 Current Current First Second density efficiency Lifespan compound compound Dopant Ratio [mA/cm²] [cd/A] [h] Example 1 1-5  2-1 Ir(ppy)₃ 75:15:10 8 41.3 121 Example 2 1-5  2-1 Ir(ppy)₃ 65:25:10 8 43.2 115 Example 3 1-5  2-3 Ir(ppy)₃ 70:20:10 8 39.3 128 Example 4 1-5  2-3 Ir(ppy)₃ 60:30:10 8 34.9 112 Example 5 1-22 2-1 Ir(ppy)₃ 30:60:10 8 39.3 89 Example 6 1-22 2-1 Ir(ppy)₃ 20:70:10 8 41.3 103 Example 7 1-22 2-3 Ir(ppy)₃ 30:60:10 8 31.2 67 Example 8 1-22 2-3 Ir(ppy)₃ 20:70:10 8 30.4 88 Comparative 1-5  — Ir(ppy)₃ 90:10 8 16.9 13 Example 1 Comparative 1-22 — Ir(ppy)₃ 90:10 8 9.8 6 Example 2 Comparative — 2-1 Ir(ppy)₃ 90:10 8 13.5 10 Example 3 Comparative — 2-3 Ir(ppy)₃ 90:10 8 6.7 23 Example 4

Referring to the data of Table 1 above, in comparison with the organic light-emitting devices of Comparative Examples 1 to 4 (including the first compound or the second compound), it may be that the organic light-emitting devices of Examples 1 to 8 (including the first compound and the second compound at the same time) had longer lifespan characteristics.

For example, the simultaneous use of the first compound and the second compound, as a host, may overcome drawbacks of each of these compounds (e.g., individually) while creating a synergy effects therebetween. Thus, the simultaneous use of the first compound and the second compound, as a host included in the emission layer, may relieve electron-induced stress in the emission layer and accordingly, may help improve a lifespan of the organic light-emitting device and a balance between the electrons and the holes, resulting in the achievement of a high efficiency of the organic light-emitting device.

As described above, according to the one or more of the above exemplary embodiments, use of a first compound represented by Formula 1 and a second compound represented by Formula 2 (e.g., as a host along with a dopant) in an emission layer may provide an organic light-emitting device having improved efficiency and lifespan characteristics.

The embodiments may provide an organic light-emitting device having improved efficiency and lifespan characteristics.

Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims. 

What is claimed is:
 1. An organic light-emitting device, comprising: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, wherein the organic layer includes: a first compound represented by Formula 1, below, and a second compound represented by Formula 2, below,

wherein, in Formulae 1 and 2, Naph is a naphthylene group, L is a C₆-C₄₀ arylene group or a C₁-C₄₀ heteroarylene group, HAr is a group represented by one of Formulae 3 and 4 below,

wherein, X₁ and X₂ are each independently N or C—*, and at least one of X₁ and X₂ is C—*, X₃ and X₄ are each independently N or CH, x₁ and y₁ are each independently 0 or 1, x₂ and y₂ are each independently 0 or 1, R₁ to R₈ are each independently selected from a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₂-C₂₀ alkenyl group, a substituted or unsubstituted C₂-C₂₀ alkynyl group, a substituted or unsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₄₀ aryl group, a substituted or unsubstituted C₁-C₄₀ heteroaryl group, a substituted or unsubstituted C₅-C₄₀ aryloxy group, a substituted or unsubstituted C₅-C₄₀ arylthio group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom or a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; at least one substituent of the substituted C₁-C₂₀ alkyl group, the substituted C₂-C₂₀ alkenyl group, the substituted C₂-C₂₀ alkynyl group, the substituted C₁-C₂₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₄₀ aryl group, the substituted C₁-C₄₀ heteroaryl group, the substituted C₅-C₄₀ aryloxy group, the substituted C₅-C₄₀ arylthio group, the substituted C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, and the substituted C₆-C₄₀ monovalent non-aromatic heterocondensed polycyclic group is selected from: a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₄₀ aryl group, a C₁-C₄₀ heteroaryl group, a C₅-C₄₀ aryloxy group, a C₅-C₄₀ arylthio group, a monovalent C₆-C₄₀ non-aromatic condensed polycyclic group, a monovalent C₆-C₄₀ non-aromatic heterocondensed polycyclic group, and —Si(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group, a is an integer of 0 to 7, b is an integer of 0 to 2, c is an integer of 1 to 3, d to h are each independently an integer of 0 to 4, i is an integer of 0 to 3, and * represents a binding site to a neighboring atom.
 2. The organic light-emitting device as claimed in claim 1, wherein L in Formula 1 is selected from: a phenylene group, a naphthylene group, a phenanthrenylene group, and an anthrylene group; and a phenylene group, a naphthyl group, a phenanthrenyl group, and an anthryl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, C₁-C₁₀ alkoxy group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group.
 3. The organic light-emitting device as claimed in claim 1, wherein L in Formula 1 is a group represented by Formula 4 Å below:

wherein, in Formula 4A, * and *′ represent binding sites to neighboring atoms, p₁ is an integer of 0 to 4, and Z₁₁ is at least one selected from: a deuterium atom, a halogen atom, a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), in which Q₂₁ to Q₂₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and a methyl group, an ethyl group, a propyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, an anthryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃), each substituted with at least one of a deuterium atom and a halogen atom.
 4. The organic light-emitting device as claimed in claim 1, wherein L in Formula 1 is a group represented by any one of Formulae 5A to 5E below, in which * and *′ represent binding sites to neighboring atoms:


5. The organic light-emitting device as claimed in claim 1, wherein HAr in Formula 2 is a group represented by any one of Formulae 6A to 6E below:

wherein, in Formulae 6A to 6E, Z₂₁ to Z₂₃ are each independently selected from a deuterium atom, a halogen atom, a C₁-C₄ alkyl group, a C₆-C₂₀ aryl group, a C₁-C₂₀ heteroaryl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), in which Q₃₁ to Q₃₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₂₀ aryl group, q1 is an integer of 0 to 4, q2 is an integer of 1 or 2, q3 is an integer of 0 to 3, and * represents a binding site to a neighboring atom.
 6. The organic light-emitting device as claimed in claim 1, wherein HAr in Formula 2 is a group represented by any one of Formulae 7A to 7E below, in which * represents a binding site to a neighboring atom:


7. The organic light-emitting device as claimed in claim 1, wherein R₁ to R₈ are each independently selected from: a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, a hexacenyl group, —N(Q₁)(Q₂), —P(═O)(Q₃)(Q₄), —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom or a C₆-C₄₀ aryl group, and Q₅, Q₆, and Q₇ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₂₀ alkyl group, or a C₆-C₄₀ aryl group; and a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a biphenyl group, a heptalenyl group, a phenalenyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a fluoranthenyl group, a pyrenyl group, a benzofluorenyl group, a naphthacenyl group, a chrysenyl group, a triphenylenyl group, a terphenyl group, a perylenyl group, a picenyl group, and a hexacenyl group, each substituted with at least one of a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, a C₂-C₁₀ alkenyl group, a C₂-C₁₀ alkynyl group, a C₁-C₁₀ alkoxy group, —Si(Q₁₁)(Q₁₂)(Q₁₃), and —Ge(Q₁₁)(Q₁₂)(Q₁₃), in which Q₁₁ to Q₁₃ are each independently a hydrogen atom, a C₁-C₁₀ alkyl group, or a C₆-C₂₀ aryl group.
 8. The organic light-emitting device as claimed in claim 1, wherein: R₁ to R₈ are each independently selected from a deuterium atom, a halogen atom, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₇ are each independently a hydrogen atom, a C₁-C₄ alkyl group, or a C₆-C₁₀ aryl group, or R₁ to R₈ are each independently a group represented by any one of Formulae 8A to 8C below:

wherein, in Formulae 8A to 8C, Z₃₁ to Z₃₃ are each independently selected from: a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, a C₆-C₄₀ aryl group, a C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇); a C₁-C₂₀ alkyl group substituted with at least one of a deuterium atom and a halogen atom; and a C₆-C₄₀ aryl group and a C₆-C₄₀ monovalent non-aromatic condensed polycyclic group, each substituted with at least one of a deuterium atom, a halogen atom, a C₁-C₂₀ alkyl group, and a C₆-C₂₀ aryl group; r1 is an integer of 0 to 5, r2 is an integer of 0 to 7, r3 is an integer of 0 to 10, and * represents a binding site to a neighboring atom.
 9. The organic light-emitting device as claimed in claim 1, wherein: R₁ to R₈ are each independently selected from a deuterium atom and a halogen atom, or R₁ to R₈ are each independently a group represented by any one of Formulae 9A to 9J below:

wherein, in Formulae 9A to 9J, * represents a binding site to a neighboring atom.
 10. The organic light-emitting device as claimed in claim 1, wherein: c is 1, a and b are each independently 0 or 1, and d, e, f, g, h, and i are each
 0. 11. The organic light-emitting device as claimed in claim 1, wherein: R₁ and R₂ are each independently selected from: a deuterium atom, a halogen atom, a methyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, —Si(Q₅)(Q₆)(Q₇), and —Ge(Q₅)(Q₆)(Q₇), in which Q₁ to Q₄ are each independently a hydrogen atom, a methyl group, or a phenyl group; and a phenyl group, a naphthyl group, and a pentalenyl group, each substituted with at least one of a deuterium atom, a halogen atom, and a methyl group; d, e, f, g, h, and i are each 0, L is selected from: a phenylene group; or a phenylene group and a naphthylene group, each substituted with at least one selected from a deuterium atom, a halogen atom, and a phenyl group.
 12. The organic light-emitting device as claimed in claim 11, wherein HAr is a group represented by Formula
 3. 13. The organic light-emitting device as claimed in claim 11, wherein: HAr is a group represented by Formula 4, x₂ is 1, and y₂ is
 0. 14. The organic light-emitting device as claimed in claim 1, wherein the first compound represented by Formula 1 is one of Compounds 1-1 to 1-36 below:


15. The organic light-emitting device as claimed in claim 1, wherein the second compound represented by Formula 2 is one of Compounds 2-1 to 2-5 below:


16. The organic light-emitting device as claimed in claim 1, wherein the first compound and the second compound are included in the emission layer.
 17. The organic light-emitting device as claimed in claim 1, wherein a weight ratio of the first compound to the second compound is about 20:80 to about 80:20.
 18. The organic light-emitting device as claimed in claim 17, wherein the emission layer further includes a dopant, the dopant including an organometallic compound that includes iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), or copper (Cu).
 19. The organic light-emitting device as claimed in claim 1, further comprising a hole transport region between the first electrode and the emission layer.
 20. The organic light-emitting device as claimed in claim 1, further comprising an electron transport region between the second electrode and the emission layer. 